Re: Project Orion Reborn.
Posted by Wayne Smith on Feb 08, 2004 at 03:52
(203.194.41.218)Re: Project Orion Reborn. (Uncle Al)
"A minimum of 50% of the energy is simply thrown away for pointing in the wrong direction."
It still outperforms chemical by a very long margin. A 4000 ton Orion could reach orbit with only 50 tons of mass expended. It is a single stage rocket. I expect that each new generation of vehicle would achieve greater results than its predecessor.
"The efficiency of coupling to the remaining 50% (silly dream even that) to the spacecraft is trivially small. Spacecraft thrust is change of momentum. It doesn't change its momentum unless it tosses mass."
The reaction mass is built into the pulse units. I suggest you do some more reading.
"A flight test called "Put-Put" flew to a whopping 200 feet propelled by five high explosive stages. Had the same chemistry been solid propellant, it would have lofted to at least 1000 ft."
One of only two flight tests ever conducted. The first was a single charge. When proving a new technology performance is irrelevant. For a fairer comparison you should compare it to Goddards petrol rocket as that too was a pioneering effort.
"Nuclear device debris is damning. What kind of dirt trail will popping 50 or 500 nukes leave?"
Nuclear bombs are designed to be damning. These are not weapons. Pulse units would be designed for minimum residual radiation. Short lived fissionables for early ascent. Radiation opaque casings. Directional blast. Airbursts are quite clean as there is nothing to irradiate except minute traces of atmospheric dust and water vapour. The groundburst can be reduced by constructing a thick steel platform coated in 6 inches of graphite based oil. Launching straight upwards the bulk of the atmosphere is only 16km thick. The most ideal location would be antarctica where atmospheric matter is even lower. Residual fallout would be very low and most of it would either vapourise within hours or dissipate into the surrounding background levels. Only one launch is necessary. Further Orions can be built in space. The first Orion being big enough to haul all the industrial infrastructure necessary to mine and refine asteroid resources. We would be stupid not to do it. If we had continued Orion back in the 60's we would now have starships.